This invention relates to an accessible raised floor system for use in office buildings or the like.
Historically, building owners have not had to deal with tenant requirements for supplemental cooling, power and cabling, with the exception of special purpose computer or trading rooms. These special purpose rooms have been dealt with almost as if they were separate structures. Unless a building was occupant owned, a tenant had to deal with these requirements. Now, due to the changes in market economies, frequently landlords are forced to solve problems of substantial increases in power requirements, additional cooling and cable distribution.
As the use of office space has evolved since the development of personal computers (PC), there has been an escalation in the need for and frequency of re-organization and re-configuration of office space. Enormous amounts of effort and study have gone into the planning and design of office space in order to render its use more flexible and sympathetic to user functions. Most of these efforts have been concentrated in modular space planning and systems furniture engineered to accommodate PCs.
Modern day office requirements have placed burdens on heating/cooling, electrical power distribution and cabling systems which were never anticipated when even the most modern office buildings were built. The rates of office reorganization and reconfiguration have escalated from about 10% to 15%, per year U.S. averages, in the early 1990""s, to 35% to 50% in the mid 1990""s, with some companies and industries exceeding 100% per year. The technological life expectancy of local and wide area networks cabling and connectors is currently about eighteen months to two years.
Physical concentrations of PCs and other electrical enhancements such as facsimile machines, copiers, printers, scanners, and in particular, the personnel operating the equipment, have placed extra-ordinary burdens on the most sophisticated and powerful heating, ventilating and air conditioning systems. These concentrations of equipment and personnel generated heat are most frequently offset by increasing the velocity of chilled air from overhead diffusers, usually at the expense of other areas, and to the discomfort of personnel.
Traditionally and technically there have been roughly seven predominant methods of distributing heating/cooling, electrical power and cable in horizontal planes from vertical sources, whether from a building core or from other vertical chases. They have been:
1) Through a ceiling plenum;
2) Through the use of conventional raised flooring systems, as have been used in computer rooms;
3) In-floor conduits or proprietary ducts;
4) A combination of plenum and under-floor distribution through rigid conduit into poke-through outlet boxes to the floor above;
5) Through stud and drywall partitions and/or column enclosures;
6) Through power poles; and,
7) Through system furniture panels.
All of these systems require the feeding of electrical power wiring and cabling through studding, systems furniture, in-floor conduit or ducts. Convenient, horizontal retro-feeding of electrical power wiring or cabling through finished stud and dry wall partitions is particularly difficult, costly, disruptive and sometimes, impossible unless sufficient conduit has been pre-installed.
The most flexible and common of these systems has been the use of ceiling plenums. This plenum approach has severe difficulties and limitations. All work must be performed from ladders or scaffolding. Most connections to work surfaces must be through stud and dry wall partitions or so-called power poles vertically to work surface or floor levels and then distributed horizontally using more stud and dry wall partitions, systems furniture or in-floor conduit or duct.
Once additional power is in place, an undesirable result is a comparable increase in generated heat, requiring more cooling. Typically such additional heat loads have not been anticipated nor dealt with in the base building design or construction.
Localized cooling solutions are being dealt with by trying to increase the output of existing systems such as pushing more air by using higher blower velocities. Increases in air velocities result in increased noise levels and are really nothing more than cycling air more rapidly through the base system which has a finite heat absorbing capacity.
There have been proposals for retrofitted auxiliary flooring systems all of which suffer distinct disadvantages. With one proposal, a lower forced air plenum would be provided for conducting supplemental cooling air to a workspace where heat generating electronic equipment has been installed. Other flooring components would be formed to define enclosed ducts above the air plenum for power cables and communication conductors. It is necessary that these enclosed ducts have imperforate walls to prevent spread of an electrical fire. In the event of such a fire, the egress of the supplemental conditioning air from the plenum would obviously be undesirable. It is for these reasons that building codes require all wiring be encased in fire resistant conduit.
Prior proposals for supplemental flooring systems have all been excessively complex such that they required skilled installers for disproportionately long periods of time. Further, prior proposed systems have not been fully modular and had inadequate provision for access to service lines extending through such a system.
Accordingly, there is a need for a simple to install supplemental flooring system which will quickly and flexibly accommodate power cable, communication wiring, and supplemental cooling to meet the demands of both current day and future electronic equipment.
The steel embodiment as described herein in conjunction with reference to FIGS. 1 through 11 is the subject matter of U.S. Pat. No. 6,061,982, issuing on May 16, 2000. It is nonetheless disclosed in some detail to assist in understanding how the short comings of the prior art are overcome.
The flooring system of the present invention utilizes prefabricated base modules which are preferably about 3xe2x80x2 by 3xe2x80x2 in horizontal dimension. These modules are installed in side by side relationship on an existing building floor. The modules are interconnected. In a metal embodiment the interconnections are accomplished by sliding key tongues into key slots of adjacent modules. In a plastic embodiment pedestals for supporting panels have depensions which interlock with the base modules. In the metal embodiment, leveling to accommodate irregularities of the building floor is achieved by adjusting leveling screws threaded into base panels of the modules.
The base panels of the metal embodiment each have elongate corrugations which stiffen the panel in one direction. Pedestal strips with their own elongated corrugations are secured to the base panels with the corrugations of the strips and panels orthoganal to one another so that together they provide a stiff module base. The pedestal strips have a series of upstanding pedestal portions. The pedestal portions are open sided, truncated pyramids each of which has oppositely, inwardly sloping side surfaces and a flat top surface. In the preferred embodiment further strips are secured to the base panel in orthogonal relationship to the pedestal strips. The further strips have upstanding portions which nest within the pedestal portions to close the sides of the pedestal portions.
The metal pedestal strips include end half pedestals at the juncture of a pedestal with a side edge of the base panel. When the modules are installed these half pedestals are butted together such that together they form a structure corresponding to full pedestals formed intermediate the ends of the strips. Similarly, four comer pedestals together form a structure corresponding to a full pedestal.
The tapering sides of the metal pedestals are notched to receive snap in steel panels. The snap in panels collectively define a power cable chase floor and a communications chase floor each above a base floor defined by the module base panels. With the metal embodiment, the panels, like other components of the system, are preferably steel (1) to protect such things as data cabling from power cable induced magnetic fields, (2) for structural strength, and (3) for fire resistance.
The plastic embodiment has a considerable weight advantage over steel, making it easier to install and highly advantageous in those situations where floor loadings may be a problem. With the plastic embodiment, pedestals in the form of axially aligned, cylindrical segments of diminishing diameters from bottom to top are provided. Each pedestal has a set of spaced arcuate depensions which fit in mating holes in the base panels to lock the panels together. Panels for chase panels with arcuate cutouts rest atop flat horizontal surfaces between adjacent, cylindrical pedestal segments.
Working floor panels are mounted atop the pedestals. Preferably these working floor panels are reinforced, steel clad, fire resistant plywood or other suitable material to provide an appropriate base for customary floor coverings such as carpet or tile.
An alternate working floor panel material which is preferred in those applications where floor loadings permit is sold under the designation MDO sign board. The MDO product has a ground wheat compressed within a resin core between specialized industrial paper layers. This MDO product and its paper layer are sold by Pacific Coating and Laminating of Kelso, Washington. The paper material is sold under the trademark PolyBak. The core material is made by a Canadian company and sold under the trademark Isoboard.
The power cable, communications and work floor panels of the metal embodiment each have knock outs which are readily removable to provide access to cabling and wiring supported on the floors. They also provide access to fluid conduits supported on the base floor.
One of the outstanding features of the invention is the use of water conduits in combination with heat pumps for supplemental heating and cooling. Supply, return and condensate conduits are installed on the base floor to conduct supply water at temperatures of about 60xc2x0 to 90xc2x0 F. A preferred source for the cooling water is a typical cooling tower of the type which is commonly mounted atop an office building. The use of water totally obviates the need for hermetic barriers between a cooling plenum and power and communication cable chases. Moreover, since the water used is cool no pipe wrap is required.
Accordingly, the objects of the invention are to provide a novel and improved supplemental flooring system and methods of installing and operating such a system.